Traction device



Patented dan. 9, 1923.

LOUIS W. CHISM, 0F SPRINGFELD, MASSACHUSETTS.

TRACTION DE'VCE.

Application filed May 31,

To all whom t may concern: n y

Be it known'that I, Louis Vif. Cinisi/i, a citizen of the United States, residing at Springfield, in the county of Hampdenand State of Massachusetts, have invented cer# tain new and useful improvements in Traction Devices, of which the following is a specification. n

This invention relates to cross-chains or traction elements and traction units embodying said elements more particularly for use on pneumatic tires and especially valuable on the very large or giant size pneumatic tires used on heavy trucks, and is capable of use with advantage on the smaller sizes of pneumatic tires and, for that matter', on all sizes of solid tires also, the weight and ysize of the individual cross-chains being proportionatel to the size of the tire to which the particular unit is to be applied.

The object more especially in viewv is to provide a cross-chain which may be mounted on the wheel in suchmanner as to prevent,

'or to limit, peripheral` movement of the unit as a whole on the wheel and which, when thusmounted, will not heat, burn, rub, blister, cut or puncture the same, which may be readily applied to even the greatest size giant pneumatic tire while the wheel is in a mud-hole, and which may also be used on all tires, which may be used either as a part of a creeping chainor as part of an anchored unit, or unit mounted in suoli manner as to prevent, or limit, its movement peripherallyr of the wheel, which will have a relatively smooth regular surface and will have alarge bearing surface on the tire, which will be very flexible, like the usual chain, in all directions, which will have no strandsor parte to be frayed out, bent and driven into the tire, and which cannot roll to such position that its links will be presented edgewise of, and cut, the tire. A further object is to so combine a cross-chain or plurality'of crosschains of the above mentioned type with means for holding it in a relatively fixed peripheral position on the tire in such way that the holding means and the terminal links ywill not contact with the tire and so that the ends of the cross-chains -will be held in spaced relation so that they cannot be-l come bunched and so, by massing, form a lump to rub against and blister the tire.

VA still further object of my invention is lto i921. seriai No. 473,605.` f

provide an automatically positioned unit which will have no positiveconnection with the elements ofthe wheel in such manner as to limit its ability to'y creep or to be moved .iny aftransverse plane about the tire, though for convenience the tag,` chain may be passed on 'opposite sides of an intervening` spoke, shown in the drawing, for thepurpose of limiting the peripheral movement of the unit ywith relation tothe tire yand felly. The automatic action is obtained by having the tread. portion of the unit heavier than the Aagportion or other intervening part or portions, and so far as thisparticular object concerned, this is all that is necessary to attain it, so that no particular type or construction of traction element or tread element is necessary so long` as it is heavier than the other portions or parts of the unit.

@ne feature of the invention consists in f of substantially uniform twist. Another fea-k' ture is the employment of such a crosschain, that is, a multiple link cross-chain in which the relation of the cross-sectional area of the end bar of each link has a certain definite relation to the area "enclosed by said link, all of the links ofsaid cross-chain be ing of substantially the same size and shape. A further feature consists in providing an anchored traction unit, that is anchored or restricted to some extent against peripheral movement, though capable of having a wide range of `movement transversely of the wheel, for heavy truck pneumatic tires, in which unit two or more heavy cross-chains will be located very closely parallel to,and adjacent to, each other in order that in use, especially in muddy `going, they may strike against each other with hammer-like blows and so keep each other free of mudk and preventeachother from becoming clogged and the unit as a whole from becoming slick. A further feature is 'the' combining of a plurality of such traction kelements or crosschains with p anchoring means ,for holding` rthe terminals of the cross-chains in spaced relation but closely adjacent to each other in order that if the plurality of cross-chains may be longitudinally twisted about each other to provide a shortened thick pliable rope which will not have any abrupt projections to damage the tire and which may be used in this manner as a special emergency device in case the truck gets into a deep mud-hole or a. stretch of muddy road having no hrm bed or the bed of which is deeply covered with mud. A further feature is that by making the tread portion heavier than the tag chain or fastening means the chain and wheel combine so that the centrifugal force generated by the rotation ofq the wheel will throw the center of the heaviest portion in axial alignment with the exact central vertical plane of the wheel and so keep the tread portion of the unit in correct transverse position on the tire and prevent the connectingl devices, hooks or the like from working` around on the tread of the tire and eliminating all need for special anchoring devices either temporarily or permanently applied to the spokes, 'jelly or other part of the wheel.

I have set forth briefly the primary objects and some of the features et' my invention above, other objects and features will be brought out in the following detail description of my invention.

Usually traction devices are applied only to the power or drive wheels of the truck or machine, but it is found that it is especially desirable in muddy sections or in slippery going to equip all wheels, though a single unit applied to each front wheel will suftice, the advantage being that this enables the steering` wheels to take hold and bite into the sides of ruts and will enable the driver to steer the truck outof ruts and avoid followlng the path of others and the necessity of sliding and skidding where they did.

ln the accompanying` drawings:

Figure l represents a side elevation of a segment of a wheel having a giant size pneumatic tire with a traction unit of multiple link construction cross chains combined therewith Figure 2, a plan view of Figure l, looking from the hub toward the felly;

Figure 3, a detail view of a portion of one of the cross-chains shown in Figure l, the present illustration being made according to exact scale and of the actual size of a dcvice or unit actually made and tested out with satisfactory results;

Figure el, a sectional view on the line 4 4 of Fig. 3;

Figure 5, a sectional view on the line 5 5 of Fig. e;

Figure 6, a detail view of a three-strand unit, the tab-chain and cross-chains being broken away, this view being made, as to the links of the cross-chains and the holders 2 to exact scale and of one-half the actual size of a unit actually made and tested with satisfactory results, being the same device referred to with regard to Figure 3;

Figure 7, a view, on the same scale as Fig. 6, of substantially a one-half length of said unit, the tread or cross-chains of which are illustrated as longitudinally twisted about each other to form a substantially smooth thick chain rope for temporary use in special emergencies;

Figure 8, a fragmentary view of a part of the tread portion, on the same scale as Figures G and 7, of a modified unit in which the two outside cross-chains are smaller in cross-section than the central cross-chain; and

`Figure 9 represents a sectional view on the line 9 9 of Figure 8.

rlhere seems no occasion toga-dd further to the above illustration, in which two forms only of my invention are set forth, it being obvious that multiple link cross-chains of the above type may bc employed having any desired multiple of links and that as many chains vper unit, for an independent unit type of traction device, may be employed as desired and that when so arranged they will be relatively close together, or` for that matter may touch, to furnish a mat or pad which will not sink into the tire as deeply as a single cross-chain, this arrangement being especially desirable on giant pneumatic tires of heavy trucks. lt is also apparent that these independent units may be employed, if desired, with any suitable anchoring devices 'in substitution for the present tab-chains, althoughsuch additional f ibstitute anchoring devices are not at essential, but sim-ply add to the cost of the equipment, as it found that by making the tread portion of thetractionunit heavier than tl e tab-chain or other securing` means, the centrifugal force generated bythe' rotation of the wheel will throw theycenter or point of gravity' of the tread 1noi-tion radially oi'itvfard into the central vertical plane of the wheel and keep it tiere so long as the wheel is rotating, thus keeping` the traction unit in correct positionon the wheel and keeping the connecting hooks from riding around ontothe tread of the tire, and this automatic positioning action follows regardless of the type or construction or traction chain or other traction yor tread element so long as the tread element portion employed is heavier thanany other .portionpf the unit. l-lrlso, it is obvious that the particular type or construction of cross-chain herein set forth one of the features of this invention may be employed as a cross-chain of a creeping type of anti-skid or traction assemblage.

For the giant pneumatic tires it is necessary to use independent units ,anchored against peripheral movement`r ory whose more-.ment is only to a limited extent peiherallyr` with, relation to the tire and wheel lly in order that the wheel cannot move independently of the traction unit, 4but must move therewith even on steep hills irrespective of the weight of the truck and its load.r

Also, the use of'independent unit on giant pneumatic tires is preferable for many reasons among others, because the units may be applied to the wheelsl after the truck gets mired and in such circumstances that as a practical matter it would be impossible to apply any other type of traction device, also any number ot such units as required by the circumstances may be applied, in many cases one or two to each drive wheel will be ample, in otherspecial circumstances more may be desirable. 4 i

Referring now in detail to thedrawings, in which only two l'orms ot' my invention are illustrated by way olf example, it being recognized that many other' forms and varia tions may be made within the principles of of my invention'as claimed, ik designates the spokes, lil the telly, Cy the rim and D a pneumatic tire of the larger giant type.

The anti-skid or traction unit illustrated in the rst seven views comprises three crosschains l having their respective terminal links, which are of the saine series, arranged or threaded on the radially outer har of a closed loop Aor holder 2. which has its end portions of its radially inner bar. depressed or pressed toward the radially outer bar at 3 to torni two end eyes in which are located and held the terminal links of the two outer cross-chains, theintermediate portion of the radially inner bar being bent in the; formof a loop 4, the adjacentsides of rwhich prevent movement of the central crosschain on lthe radially outer bar between the shoulders 3 of the radially inner bar. l

rlhis construction guards.againstthe terminal portions ofthe,cross-chains irbecoming hunched andk .forming a stili lump that might rub against and blister the side of the tire. From actual test it'has been found that it is highly important to keep the terminal portions oi" the cross-chainsseparated to avoid the above mentioned risk.y

, lt will be noted that the series of links which threaded through the links a., and through each other approximately atK4 the middle portion ot each link a, do not bearI with their inner faces against the corresponding faces of thelinks a, but areindependent :thereof and freely suspended therein or therethrough and it is therefore'important, to insure proper arrangement ot the chain andto avoid yharmful frictional slip oi? one series o'lilinks oit the chain with re-4 lation to the other series, to have the terminal links of each cross-chain of the same seriesl being series a in the unit illustrated, and have this single series ot links t bear all pull and strain, though of course the wear incident to rictional contact with theground will be borne equally by yboth series of links. rllie links Z) are best described. as a floating or freely suspended independent series of links which, nevertheless, have a distinct re-` lation inproportion, both to size of material used and size or" individual link, to the links 'ot series a, both series having the saine degree of twist, which kwill vary somewhat `usually as between particular links but will preferably `loe withina range oli between 90 to 110` degrees measured between planes tangent at the ends of the particular links,

whereby a smooth, uniform, flat, illed or` substantially solid cross-chain or cross# chainrope is produced and which, when arranged on the wheel tire, will not become disarranged, or in which one ofthe seriesioi'' f links will not slip with relation to the other series, and so disturb the arrangement ofthe links in such manner as to leave a number ci relatively large openings between a number of huinpsot metal. This iso't decided im portance. i i f i The yproportions of each link of each series are such that, for instance in the two series link chain shown in which four links are `threaded through each link, the` diameter of the cross-section of the end of each link will be very slightly less thanone-fourth the distance between theinner faces of the end por-v tionsl of said linkI` all of said links being made so nearly as is practical of the same dimensions and form. The above propor` tions allow just sutlicient room to'permit the desired flexibility, while said ends and the adjacent `portions 'of the side bars of the links threaded through any given link substantially lill up the space defined by said link, presenting a large and relatively smooth substantially solid bearing surface of the liexible traction element for the tire tread, and producing in effect aliat chain ifo e. threaded through a link be increased then the proportions will vary in accordance with the number yof links and the number of series o'flinks will be increased bv one-halt of the number 'of additional links threaded through a given link.

In the particular form of unit actually illustrated, to the intermediate loop 4 of one of the holders 2 is connected the tab or anchoringior securing chain, preferably by havingone of the terminal loops oi' the tab-y chain 5 formed aiound they radially inner bar of such holder 2 during the manufacture or assembly ofthe unit To apply the particular form of unit shown to awheel, the crosschains are pret- Ot Acourse il:l the number of linksy links ca ot the chains l connected to the holders2, to guard against rubbing against the tire by the holders Q or the terminal links a. oi the cross-chains, which terminal links, because oi' their connection to the holders 2, are slightly limited in motion yor stiff, andalso te guard against rubbing against thetire by thetab-chain 5. The tab chain is then passed through the Wheel on one side ot said spoke, threaded througl'i the intermediate loop dl of the holder 2 to which it is not permanently attached., then brought back through the wheel en the other side et said speke and drawn tight, the conneet-or being threaded into the nearest. link et the tab-chain to the loop l ot the lirst mentioned holder and then this connector E' is hooked into loop fl ot this holder 2. This arrangement will limit the peripheral, er practically prevent, the peripheral, movement ot' the unit with relation to the Wheel. @t course it is not essential that the tab chain 5 illustrated be employed, or that, if used, either ot its be permanently connected to either holder 2, nor is it essential that the particular-term. out connector E illustrated be used. lVhile this connector has given satisfactory results,

other forms of connectors will sul-lice.

In the modification shown in Figures 8 and '9, bykway of Jiurther example only, the construction and operation and mode ot application are the sameL as in the form above described, except that the tvo outer cross-chains l ot the said above described 'form are replaced by cross-chains ln considerably smaller in cross-section than central cross-chain l, this construction resulting'r in forming a unit, the traction portion ot which will slope from the center toward each side and so will substantially reduce the shock or jar caused by the traction portion as it strikes and leavesthe ground.

Having thus described my invention, what l claim as new and desire to secure by Letters Patent is:

l. A Wheel and a tire mounted thereon, in combination with a traction device mounted on said Wheel and comprising` a cross-chain, extending` across the tread ot the tire and consisting' ot two series ot' longitudinally interthreaded twisted links, and means connected to the terminal links ot one ot said series of links tor securing said cross-chain in mounted relation upon the wheel, whereby the links of each series are lett undisturbed with relation tothe links ot the other series and a uniform iat surface Will be presented to the tire tread tace.

2. A cross-chain for arrangement across the tread ot a Vehicle tire, said cross-chain comprising a plurality of longitudinally arranged interthreaded links,veach link, eX- cept the links at the end portions, having at least tour other links threaded through it, the cross-sectional area of each end ot ach link with relation to the area enclosed by said link being determined by the number et' similar links threaded therethrough While just leaving sutiicient room t'or the individual links to turn on each other to permit flexing o'l" Athe chain, whereby the cross-chain is termed with a composite substantially unbroken surface for engagement by the tire without sacrificing Hexibility ot' the achain.

il. travtion device for arrangement on a wheel and con A)rising a plurality or crosschains for arrangement across the tread ot the tire thereof, each ci chain consisting el a plurality ot longitiulinally arranged imei-threaded links, each link, except the links at the end portions, having at least tour other links threaded through it, the cross-sectional area oi' each end of each link with relation te the area enclosed by said lint: being' determined by the number of similar link* threaded therethrough While leaving just suiiicient room for the individual lin? 1 to turn on each other to permit llc-Xing ci the chain, whereby each cross-chain is formed with a composite substantially unbroken surface for engagement by the tire Without sacrificing iiexbility ol the chain.

l. A Wheel and a tire thereon, in combination vwith a traction device mounted on said Wheel and comprising a cross-chain extending across the tread ot said tire and consisting of tivo series ot' longitudinally interthreaded links,.each link ot' each series being` gir/'en a substantially unil-erm twist ot at least 90 degrees measured between planes tangent at the ends of the particular links, saidlinks all being twisted in the same direction, and each `link 'of both series beingl substantially ot the same size, proportions and shape as each of the other links of both of said series, whereby a flat smooth surface of a flexible rope-like chain is presented to the surface of the tire.

5. An independent traction vunit for arrangement on a Wheel and comprising a pluralityot cross-chains, in arranged relation, extending across the tread of the Wheel tire, each cross-chain consisting of a plurality of series ot lonofitudinally interthreaded twisted links, and means connected to the terminal links of one of said series of links of the respective cross-chains for anchoring said cross-chains on the Wheel, whereby the links ot each ot said series are lett undisturbedwith relation to the links of the other series and a uniform flat surface will be presented to the tire, the said means being formed .to hold said terminal links of the respective cross-chains in spaced arrangement closely adjacent to each other in order that in special conditions of the road the cross-chains may b'e longitudinally twisted about each other and combine with eaeh other to forni a single relatively smooth, thick, chain-rope.

6. A wheel and a tire thereon, in combination with a traction device mounted on said wheel and comprising a traction element comprising end portions consisting of two series of longitudinally interthreaded twisted links, and means connected to the terminal links of one of said series of links of each end portion for connecting said traction element across the tire and for securing said traction element in mounted relation on said wheel, whereby the links or each series of links of each end portion of the traction element are left undisturbed with relation to the links of the other series and a uniform flat surface will be presented toward the tire.

7. A wheel and a tire thereon, in combination with a cross-chain for arrangement across the tread of said tire, said cross-chain comprisinga plurality of series oit' longitudinally interthreaded links, each link, except the links at the end portions, having at least four other similar through it, the cross-sectional area of each end of each link with relation to the area enclosed by the said link lbeing determined links threaded by the number oi similar links threaded therethrough while leaving just sufficient room for the individual links `to turn on each other to permit flexing of the chain, all of said links having a substantially uniform twist. f

8. A cross-chain for arrangement across the tread of a vehicle tire, said cross-r chain Comprising ya plurality of series of longitudinally interthreaded twisted links, one or said series or said links being freely suspended in another of said series, and means connected to the respective terminal links of the latter seriesor securing said cross-chain transversely across the tread of the tire, whereby the links of each series will chain', and means for holding the terminal portions oi such cross-chains in arranged relation. i y

LOUIS W; CHISM. 

